The Queens, New York, location of the restaurant also has a sign that said, "Boooooo. Just kidding. We still flame grill our burgers. Happy Halloween."

Ouch.

Whether or not McDonald's will respond isn't clear. If the past is any indication, though, it will not.

When Burger King challenged McDonald's to team up to combine their signature burgers -- the Whopper and Big Mac, respectively -- in 2015, McDonald's CEO Steve Easterbrook declined the offer in a Facebook post, saying, "We love the intention but think our two brands could do something bigger to make a difference. ... (L)et's acknowledge that between us there is simply a friendly business competition and certainly not the unequaled circumstances of the real pain and suffering of war. ... P.S.: A simple phone call will do next time."